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The singlet oxygen could be generated over a novel Fenton-like CeO2/CN catalyst via Ce4+/Ce3+ redox for the first time in dark and was utilized to efficiently degrade the emerging pollutant of TCH in a wide pH value (1.20–11.20).

For the first time, an industrial solid waste (CAS) was used for the rapid oxidation and neutralization of acidic sulfate soil. The waste mainly contained Fe-doped CaCO3 and CaAl-layered double hyd...

BNT162b1 is a lipid nanoparticle-formulated, nucleoside-modified mRNA SARS-CoV-2 vaccine. Here, we report safety and immune persistence data following a primary two-dose vaccination schedule administered 21 days apart.Immune persistence was determined at month 3 in 72 younger participants (aged 18-55 years) and at month 6 in 70 younger and 69 older participants (aged 65-85 years).In younger participants, neutralizing antibody (nAb) geometric mean titers (GMTs) for the 10 and 30 µg dose levels declined from 233 and 254 (21 days after dose 2) to 55 and 87 at month 3, respectively, and to 16 and 27 at month 6, respectively. In older participants, nAb GMTs declined from 80 and 160 (21 days after dose 2) to 10 and 21 at month 6. Overall, higher antibody titers were observed in younger participants, and the 30 µg dose induced higher levels of nAb, which declined more slowly by month 6. No serious adverse events were reported in the vaccine group.This study showed BNT162b1 maintains a favorable safety profile in younger and older participants in the 6 months after vaccination. This study further extends our understanding of immune persistence and the safety of the BNT162b1 vaccine as a candidate vaccine in the BioNTech pipeline.NCT04523571, registered August 21, 2020.

LSTM network is an effective RNN model to predict the system RUL for its superior performance in sequential data processing. Usually, networks trained by life-cycle labeled dataset would possess similar RUL predicting accuracies, because the network training algorithm could ensure the network optimality for the whole training dataset. However, for networks trained by non-life-cycle labeled samples, the network uncertainty caused by different training conditions could lead to degradation prediction uncertainty for some local points. Further, the RUL predicting results that are computed by these uncertain local points may shows relatively large differences. Therefore, in order to obtain an accurate RUL prediction with networks trained by non-life-cycle labeled samples, our paper proposes a novel network model averaging method to deal with the network uncertainty. What is more, to learn the temporal correlation information of training samples sufficiently, we adopt the Bi-LSTM network to illustrate the application of the proposed network model averaging method. Finally, degradation values of Graphite/LiCoO2 battery are used to verify the effectiveness of the proposed method. The results show that the proposed method could improve the RUL prediction accuracy and reduce the prediction error.

The current paper investigates energy-constraint formation design and analysis problems for multiagent systems with two types of switching interaction topologies; that is, leaderless ones and leader-following ones. Firstly, a new formation control protocol with switching interaction topologies is shown, where the whole energy supply is limited previously. Then, by constructing the relationship of the whole energy supply and the matrix variable, sufficient conditions for leaderless energy-constraint formation design and analysis are respectively presented by the linear matrix inequality tool. Furthermore, an approach is proposed to determine an explicit expression of the formation center function, which determines the macroscopic motion of a multiagent system as a whole and consists of two parts: the initial state term and the formation function term. Moreover, main conclusions of leaderless energy-constraint formation are extended into leader-following multiagent systems by a new two-step transformation approach, where the asymmetric structure feature of leader-following switching interaction topologies is well dealt with. Finally, two numerical examples are provided to demonstrate the effectiveness of main conclusions.

This study was aimed to describe the standardized treatment rate of syphilis-infected pregnant women in Hunan province and to explore the determinants for standardized treatment. All syphilis-infected pregnant women registered in the Information System of Prevention of Mother-to-Child Transmission of Syphilis Management (IPMTCT) in Hunan between January 2015 and December 2018 were included in this study. Among 9,059 pregnant women with syphilis, 7,797 received syphilis treatment, with a treatment rate of 86.1%, and 4,963 underwent standardized syphilis treatment, with an average standardized treatment rate of 54.8%. The facilitators for the standardized treatment included abnormal reproductive histories (aOR = 1.15, 95%CI:1.03–1.28), time of first prenatal care within 1–12 weeks (aOR = 5.17, 95%CI:4.19–6.37) or within 13–27 weeks (aOR = 5.56, 95%CI:4.46–6.92), previous syphilis infection (aOR = 1.64, 95%CI: 1.48–1.81), and definite syphilis infection status of sexual partner (negative: aOR = 1.73, 95%CI:1.57–1.91; positive: aOR = 1.62, 95%CI:1.34–1.95). The barriers included marital status being unmarried/divorced/widowed (aOR = 0.81, 95%CI: 0.65–0.99), pluripara (aOR = 0.58, 95%CI: 0.46–0.74), number of children ≥ 2 (aOR = 0.45, 95%CI: 0.35–0.57), and syphilis clinical stage being primary/secondary/tertiary (aOR = 0.72, 95%CI: 0.58–0.88) or unclear (aOR = 0.78, 95%CI: 0.70–0.86). Though the treatment rate of syphilis-infected pregnant women was high, the standardized treatment rate was low. The facilitators and barriers on standardized treatment of gestational syphilis were identified at the patient level.

Background In recent 10 years, with the rapid socioeconomic development and the extensive implementation of children nutrition improvement projects, the previous epidemiological data cannot reflect the actual level of anemia among children in China, especially in rural areas. Therefore, this study analyzed the prevalence, severity and associated factors of anemia among children aged 6–71 months in rural Hunan Province. Methods A community-based cross-sectional study was conducted. Through multistage stratified cluster sampling, 5229 children aged 6 to 71 months and their caregivers were randomly selected from 72 villages across 24 towns in 12 counties from rural Hunan. The demographic characteristics of children and their caregivers, feeding practice, nutritional status of children, caregivers’ anemia-related feeding knowledge, and gestational conditions of mothers were acquired by using a unified questionnaire. Peripheral blood from the left-hand middle fingertip was sampled from each child, and hemoglobin concentration was measured using a HemoCue301 portable hemoglobin analyzer (Sweden). Associated factors analyses involving overall anemia and anemia severities were conducted on multivariate logistic regression models. Results The overall anemia prevalence was 8.8%, and the prevalence of mild, moderate and severe anemia was 6.3, 2.5 and 0.1%, respectively. Children age groups of 6–11 months, 12–23 months and 36–47 months, exclusive breast-feeding within 6 months after birth, and maternal moderate/severe anemia were significantly associated with an increased risk of overall anemia in children. Children age groups of 6–11 months and 12–23 months were significantly associated with an increased risk of mild anemia in children. Children age groups of 6–11 months, 12–23 months and 36–47 months, low caregivers’ anemia-related feeding knowledge level, and maternal moderate/severe anemia were significantly associated with an increased risk of moderate/severe anemia in children. Children who underwent regular physical examination were less likely to have moderate/severe anemia. The common protective factor for overall, mild and moderate/severe anemia in children was high family income. Conclusions The anemia status of preschool children in rural Hunan Province was a mild public health problem and associated with children age group, feeding practice, regular physical examination, family income, caregivers’ anemia-related feeding knowledge level, and maternal moderate/severe anemia.

A multi-dimensional (1D/2D/3D) carbon/g-C3N4 composite photocatalyst (CCN) was successfully prepared by a facile method with carbon from cheap absorbent cotton wool. The activities and stabilities of CCN were evaluated by photo-degrading Rhodamine B (RhB) under visible light irradiation. The effect of carbon content in composite on the catalytic activities was investigated. The results show that a good interfacial contact can be observed between g-C3N4 and carbon materials in CCN. It reveals an enhanced photocatalytic activity in photocatalytic decomposition of RhB compared with g-C3N4. The carbon content has obvious effect on the performance of CCN, and the optimal carbon content in CCN is 1 wt% (CCN1.0). The first-order rate constant (k) of CCN1.0 is approximately 5.5 and 3.4 times those of g-C3N4 and AC1.0/g-C3N4. The CCN1.0 catalyst also shows the excellent photocatalytic stability in the recycling experiments. The enhanced catalytic performance of CCN is mainly due to an increase in electron-hole pair separation efficiency and visible light adsorption after coupling carbon. The hole and •O2– radicals are the main active species, and •O2– plays a more important role than h+. The photocatalytic mechanism over CCN1.0 was proposed. This work will provide a new insight to prepare highly-efficient g-C3N4-based photocatalysts.

Prognostics and health management (PHM) technology is an extremely important research focus in the field of reliability engineering. The ultimate goal of applying PHM technology is health management. Aiming at nonlinear degradation systems, an adaptive maintenance policy based on prognostic information is proposed herein. First, a nonlinear degradation model with an adaptive updating mechanism is used to predict the remaining useful life (RUL) of the degrading system. Then, based on the predicted RUL distribution, a multi-objective optimization model is established to address the trade-off between operating cost and availability through a constructed decision boundary, instead of the approach used in previous studies, which considers cost as a single indicator. Using this multi-objective optimization model, an adaptive decision criterion is proposed to evaluate the advantages and disadvantages of different replacement policies, in order to determine the optimal replacement time and dynamic condition monitoring (CM) interval of the degrading system. Finally, an example of gyroscope in an inertial navigation system (INS) is used to verify the effectiveness of the proposed method.

Apoptosis of alveolar epithelial cells is a critical initial link in the pathogenesis of acute lung injury (ALI), recent studies have revealed that Methyl-CpG binding domain protein 2 (MBD2) was involved in the execution of apoptosis, yet its role in ALI remained unclear. In the present study, we aim to explore the role and mechanism of MBD2 in the pathogenesis of ALI. We have found that MBD2 expression, in parallel to apoptosis, increased in alveolar epithelial cells of mice treated with LPS, knockout of MBD2 reduced apoptosis and protected mice from LPS-induced ALI. In MLE-12 cells, a cell line of murine alveolar epithelial cells, LPS induced MBD2 expression and apoptosis in a dose- and time-dependent manner. Knockdown of MBD2 with shRNA alleviated, while overexpression of MBD2 increased LPS-induced apoptosis. Mechanistically, intracellular zinc level decreased when MLE-12 cells were treated with LPS. MBD2 knockdown restored intracellular zinc level after LPS treatment, and MBD2 overexpression further aggravated LPS-induced intracellular zinc loss. Metal transcription factor 1 (MTF1) is a critical transcription factor in charge of intracellular zinc efflux. LPS treatment induced MTF1 expression both in vivo and in vitro. Inhibition of MTF1 reduced LPS-induced apoptosis in MLE-12 cells. MBD2 could bind to the promoter region of MTF1 and promote MTF1 expression. Collectively, these data indicated that loss of MBD2-ameliorated LPS-induced alveolar epithelial cell apoptosis and ALI in mice via modulating intracellular zinc homeostasis by upregulating MTF1.

Evaluation of the anti-jamming effect of synthetic open radar (SAR) is an important problem in the electronic war. Existing evaluation methods generally use the method of controlling the interference index of Image SAR. When the SAR image quality is poor, the performance of these methods will decline. To solve the above problems, a comprehensive evaluation method based on multi-attribute decision-making theory is proposed. Firstly, the SAR anti-jamming evaluation model is established. On this basis, a new evaluation index system is proposed. It consists of a signal layer, an image layer and a decision layer. The relative weight of each index shall be determined by a combined weighing method. Finally, the anti-jamming performance of SAR is evaluated by using elector III. The correctness and rationality of the model and evaluation method are verified by simulation.

Background Early prediction of hospital mortality is crucial for ICU patients with sepsis. This study aimed to develop a novel blending machine learning (ML) model for hospital mortality prediction in ICU patients with sepsis. Methods Two ICU databases were employed: eICU Collaborative Research Database (eICU-CRD) and Medical Information Mart for Intensive Care III (MIMIC-III). All adult patients who fulfilled Sepsis-3 criteria were identified. Samples from eICU-CRD constituted training set and samples from MIMIC-III constituted test set. Stepwise logistic regression model was used for predictor selection. Blending ML model which integrated nine sorts of basic ML models was developed for hospital mortality prediction in ICU patients with sepsis. Model performance was evaluated by various measures related to discrimination or calibration. Results Twelve thousand five hundred fifty-eight patients from eICU-CRD were included as the training set, and 12,095 patients from MIMIC-III were included as the test set. Both the training set and the test set showed a hospital mortality of 17.9%. Maximum and minimum lactate, maximum and minimum albumin, minimum PaO2/FiO2 and age were important predictors identified by both random forest and extreme gradient boosting algorithm. Blending ML models based on corresponding set of predictors presented better discrimination than SAPS II (AUROC, 0.806 vs. 0.771; AUPRC 0.515 vs. 0.429) and SOFA (AUROC, 0.742 vs. 0.706; AUPRC 0.428 vs. 0.381) on the test set. In addition, calibration curves showed that blending ML models had better calibration than SAPS II. Conclusions The blending ML model is capable of integrating different sorts of basic ML models efficiently, and outperforms conventional severity scores in predicting hospital mortality among septic patients in ICU.

To probe into the associations between maternal personal cosmetics use during pregnancy and risk of adverse outcomes, and explore the potential dose-response relationships, we carried out a prospective cohort study involving 9710 pregnant women in Zhuzhou City and Xiangtan City in Hunan province during 2016–2017. A structured questionnaire was used to collection information for the pregnant women and their pregnancy outcomes. Odds ratios (OR) and 95% confidence intervals (CI) were calculated by binary or multinomial logistic regressions. The study population included 4652 (47.9%) cosmetics non-users and 5058 (52.1%) cosmetics users. Cosmetics use was associated with an increased risk of small for gestational age (SGA) (aOR = 1.23, 95%CI 1.04 to 1.44), compared with cosmetics non-users. A positive dose-response relationship between frequency of cosmetics use and SGA was observed, although a borderline association was found at low use frequency (1–2 times per week; aOR = 1.18, 95%CI 0.99 to 1.40) and moderate use frequency (3–4 times per week; aOR = 1.23, 95%CI 0.92 to 1.64). High-frequency of cosmetics use (≥5 times per week) was significantly correlated with a higher risk of SGA (aOR = 1.83, 95%CI 1.25 to 2.69). No significant association between personal cosmetics use and the risk of preterm birth, low birth weight, macrosomia, or large for gestational age was observed. The present study suggests that personal cosmetics use will increase the risk of SGA, but further research is required to determine which cosmetic products may account for the higher risk of SGA.

As the fundamental and prerequisite work of remaining useful life (RUL) prediction, degradation modeling directly affects the accuracy of RUL prediction. Existing degradation models are all developed under a single time scale, and less research has been carried out to consider the impact of multiple time scales on the degradation model. Toward this end, we mainly study a nonlinear degradation modeling and RUL prediction method for nonlinear stochastic degraded equipment with bivariate time scales in this paper. Firstly, a nonlinear degradation model considering the influence of two time scales is constructed based on the diffusion process. At the same time, the relationship between the two scales is quantitatively characterized by random proportional coefficient. Then, the analytical expressions of the life and RUL for nonlinear degraded equipment are derived under the concept of first passage time (FPT). In order to realize the adaptive estimation of parameters, the model parameters estimation method based on maximum likelihood estimation (MLE) and Kalman filtering algorithm is developed in this paper. Finally, numerical simulation and the monitoring data of gyroscope verify the effectiveness and superiority of the proposed method. The experimental results show that the method proposed in this paper can effectively improve the accuracy of RUL prediction, and has a broad engineering application space.

Remaining useful life (RUL) estimation is the key of prognostics and health management (PHM) technology and is an effective way to ensure the safe and reliable operation of equipment. Aiming at the lack of historical data and prior information for the newly developed small-sample systems, an adaptive RUL estimation method based on the expectation maximization (EM) algorithm is proposed with three-source variability. First, a degradation model based on a Wiener process is established to incorporate three-source variability and dynamic sampling interval, and the analytical solution of RUL distribution is derived in the sense of the first hitting time. Second, an adaptive parameter estimation method based on the EM algorithm is proposed to update the model parameters by using the condition monitoring (CM) data from one working system running up to the current moment. Finally, a practical example of a gyroscope in an inertial navigation system is provided to substantiate the effectiveness and superiority of the proposed method. The results indicate that the proposed method can efficiently improve the accuracy of the RUL estimation.

For the first time, Coral sand, as the main geotechnical material in reclamation, has the characteristics of loose and porous structure, relatively small volume and mass, easy to break and high compression, and high calcium carbonate, which may be a natural material to control acid release of acid soil. In this paper, by studying the neutralization effect of coral sand under different sand ratio, particle size and adding methods, the optimal dosage and particle size of coral sand and the adding sequence were determined under typical acid soil conditions; The neutralization performance of different neutralizing materials was compared through internal structure characterization, and the structural advantages of coral sand were explored. The results show that the specific surface area of coral sand was 1.2361m2g-1, second only to calcite and shell powder. The particles were evenly distributed and can fully react with sulfuric acid to produce CaSO4 precipitation. When the addition of coral sand was 9% (Ca: S = 18:5), the PASS can be neutralized to pH > 6.5. The PASS neutralization ability of coral sand was related to particle size. The overall trend was that the smaller the particle size, the stronger the neutralization ability. The best effect was at 0.15mm, when the particle size exceeded 0.27mm, the neutralization ability began to decline.

Online remaining-useful-life (RUL) estimation is an effective method with respect to ensuring the safety of complex-huge systems. Generally, current methods assume a specific degradation model when degradation values are observed in the initial degradation phase. However, this assumption may not always be robust enough owing to the often-ambiguous inherent incipient-degradation characteristic. Therefore, besides model-parameter uncertainty, the uncertainty of the degradation model is worth examining in online RUL estimations. In this paper, a Bayesian-updated expectation-conditional-maximization (ECM) algorithm is adopted to address the uncertainty of prior parameters, and a modified Bayesian-model-averaging method is used to deal with the uncertainty of the degradation model. Then, simulation studies are conducted to analyze the effectiveness of the proposed fusion algorithm. Results suggest that the Bayesian-updated ECM algorithm and modified Bayesian-model-averaging method effectively address the associated uncertainties of model parameters and the degradation model itself. Finally, we apply the proposed fusion algorithm to predict the RUL of a gyroscope.

Background In recent ten years, with the rapid socioeconomic development and the extensive implementation of children nutrition improvement projects, the previous epidemiological data cannot reflect the actual level of anemia among children in China, especially in rural areas. Therefore, this study analyzed the prevalence, severity and associated determinant factors of anemia among children aged 6-71 months in rural Hunan Province. Methods A community-based cross-sectional study was conducted. Through multistage stratified cluster sampling, 5229 children aged 6 to 71 months and their caregivers were randomly selected from 72 villages across 24 towns in 12 counties from rural Hunan. The demographic characteristics of children and their caregivers, feeding practice, caregivers’ anemia-related feeding knowledge, and gestational conditions of mothers were acquired by using a unified questionnaire. Peripheral blood from the left-hand middle fingertip was sampled from each child, and hemoglobin concentration was measured using a HemoCue301 portable hemoglobin analyzer (Sweden). Associated determinant factors analyses involving overall anemia and anemic severity were conducted on multivariate logistic regression models. Results The overall anemia prevalence was 9.7% (506/5229), and the prevalence of mild, moderate and severe anemia was 6.7% (349/5229), 2.9% (151/5229) and 0.1% (6/5229), respectively. Children age groups of 6-11 months, 12-23 months and 36-47 months, exclusive breast-feeding within 6 months after birth, and maternal moderate/severe anemia were significantly associated with an increased risk of overall anemia in children. Children age groups of 6-11 months and 12-23 months, maternal moderate/severe anemia were significantly associated with an increased risk of mild anemia in children. Children age groups of 6-11 months, 12-23 months and 36-47 months, lower caregivers’ anemia-related feeding knowledge level, and maternal moderate/severe anemia were significantly associated with an increased risk of moderate/severe anemia in children. Children who underwent regular physical examination were less likely to have moderate/severe anemia. The common protective factor for overall, mild and moderate/severe anemia in children was high family income. Conclusions The anemia status of preschool children in rural Hunan Province was a mild public health problem and associated with children age group, feeding practice, regular physical examination, family income, caregivers’ anemia-related feeding knowledge level, and maternal moderate/severe anemia.

Additional file 1. The corrected values of hemoglobin at different altitudes.

Objective. Allergic asthma is a chronic inflammatory disease, which seriously affects the life quality of patients, especially children. Alanylglutamine is a nutritional supplement with potential protective and anti-inflammatory effects, but its function in allergic asthma remains elusive. In this study, we focused on the investigations of the roles and functional mechanism of Alanylglutamine in asthma. Methods. Ovalbumin (OVA) induction was utilized to establish a mouse asthma model. 16S rDNA sequencing was performed to compare the diversity of intestinal microorganisms under different treatments. Gas chromatography was utilized to screen the intestinal microbe-short-chain fatty acids in the stool. The lung tissue was extracted to determine signaling pathways, including AMPK, NF-κB, mTOR, STAT3, IKKβ, TGF-β, and IL-1β through Western blot or RT-qPCR. Results. It was observed that Alanylglutamine reduced the cytokine in OVA-induced allergic asthma mice. H&E staining showed obvious pneumonia symptoms in the asthma group, while Alanylglutamine alleviated the inflammatory infiltration. Alanylglutamine reversed gut microbiota compositions in OVA-induced allergic asthma mice and enhanced the butyric acid level. The protective role of Alanylglutamine may be associated with the gut microbiota-butyric acid-GPR43 pathway in asthma mice. In contrast to the OVA group, Alanylglutamine activated the protein expression of P-AMPK/AMPK and inhibited the protein expression of P-mTOR/mTOR, P-P65/P65, P-STAT3/STAT3, P-IKKβ/IKKβ, TGF-β, and IL-1β, with similar effects from butyric acid. Conclusion. The results indicated that Alanylglutamine might be beneficial for asthma, and its effect was achieved through the regulation on microbiota and the derived metabolites. The therapeutic effects might be associated with AMPK, NF-κB, mTOR, and STAT3 signaling pathways. These findings will help identify effective therapeutic direction to alleviate allergic inflammation of the lungs and airways.

A flexible Pt/TiO2/γ-Al2O3 nanfiber paper (PTA) was successfully prepared by an electrospinning-coating-NaBH4 reduction method. The catalytic performance for formaldehyde (HCHO) oxidation over PTA with different Pt contents was investigated at room temperature. The results show that PTA exhibits higher catalytic activity and stability than Pt/γ-Al2O3. The TiO2 coating can promote the transformation of intermediate species and the desorption of CO2. The PTA1 with 1 wt% Pt shows the best catalytic activity and good stability. In the view of activity and cost, 0.5 wt% Pt is the optimal Pt content. The TiO2 coating not only plays an important role in improving the activity and stability of PTA, but also acts as a protective shell of γ-Al2O3 fiber, which greatly reduces the risk of alkali etching during preparation and maintains the good flexibility of PTA. The dioxymethylene (DOM), formate/carbonate species, CO are the intermediate species in HCHO oxidation over PTA. In addition, PTA exhibits good filtration performance for fine particles as well as good fluid permeability. Because of the high efficiency and flexibility of PTA composite catalytic material for HCHO oxidation with good filtration performance for fine particles, it will be a promising candidate in air purification.

Heterogeneous Fenton-like reaction has been extensively investigated for degradation of organic pollutants for waste treatment due to the formation of highly aggressive hydroxyl radicals from hydrogen peroxide. However, most heterogeneous Fenton-like catalysts still worked well under acid conditions/or with the help of light irradiation/ electrical field, which limits their applications. Here, a novel Fenton-like catalyst of Ag3PO4/g-C3N4 was used for degradation of tetracycline hydrochloride (TCH, a typical emerging aqueous pollutant) for the first time in a wide pH value range (4.04–9.08) in dark. The results showed that it could effectively activate H2O2 to generate ⋅OH and ⋅O2– radicals in dark, which could oxidize the target pollutant in the all testing pH value range. It also showed a good stability in repeating test. The results of characterizations and theory calculation revealed a strong electronic interaction between Ag3PO4 and g-C3N4 improving the electron densities around Ag and O atoms in Ag3PO4 on the interface, which benefited the formation of active species. This work is expected to provide an insight for the design and fabrication of the novel highly-efficient Fenton-like catalysts for purification of waste water in a wide pH range.

A multi-dimensional (1D/2D/3D) carbon/g-C

The reduction of protein translation is a common feature in senescent cells and aging organisms, yet the underlying mechanisms are not fully understood. Here we show that both global mRNA translation and mammalian/mechanistic target of rapamycin complex 1 (mTORC1) kinase activity are declined in a senescent model of mouse embryonic fibroblasts (MEFs). Furthermore, RNA-seq analyses from polysomal versus total mRNA fractions identify TOP-like mRNA of Rps15 whose translation is regulated by mTORC1 during MEF senescence. Overexpression of Rps15 delays MEF senescence, possibly through regulating ribosome maturation. Together, these findings indicate that the activation of mTORC1-Rps15 axis ameliorate senescence by regulating ribosome biogenesis, which may provide further insights into aging research.

Two novel species of Russula subgenus Heterophyllidia, collected from Guangdong Province, P. R. of China, are described and illustrated based on both morphology and phylogenetic analyses of ITS sequences. Russula verrucospora sp. nov. is characterized by a combination of unequal lamellae, verrucose basidiospores, presence of robust caulocystidia, and pleurocystidia changing to reddish-brown in sulphovanillin (SV). R. xanthovirens sp. nov. is phylogenetically closely related to R. aureoviridis within subsection Virescentinae, but it can be separated from the latter by its much thicker pileipellis which is distinctly divided into two layers and orthochromatic in cresyl blue, ellipsoid to globose subterminal cells, bigger basidiospores with higher warts and ridges, and much longer pleurocystidia and cheilocystidia. Both morphological and molecular data consistently verify that R. verrucospora and R. xanthovirens are new to subg. Heterophyllidia. The differences among these two novel species and their related taxa are discussed.